Mast cells in melanocytic skin lesions : an immunohistochemical and quantitative study

The mast cells participate in inflammation and possibly in carcinogenesis. The aim of the study was to study mast cells in melanocytic lesions. The material consisted of 24 pigmented nevi, 18 dysplastic nevi and 19melanomas. The sections were stained immunohistochemically for tryptase and chymase. Positive cells were counted inside the lesions and at the interface between the lesion and dermis. The mean intralesional tryptase+count was 15.75 for nevi, 21.78 for dysplastic nevi, and 8.07 for melanomas. The chymase+intralesional count was 14.89 for nevi, 21.88 for dysplastic nevi, and 11.34 for melanomas. The tryptase+ perilesional count was 16.89 for nevi, 15.93 for dysplastic nevi, and 15.71 for melanomas. The chymase+ perilesional count was 16.52 for nevi, 16.16 for dysplastic nevi, and 14.77 for melanomas. The tryptase/chymase intralesional ratio was 0.93 for nevi, 1.05 for dysplastic nevi, and 1.67 for melanomas. The tryptase/chymase perilesional ratio was 1.02 for nevi, 1.09 for dysplastic nevi, and 1.00 for melanomas. The differences between intralesional mast cells, both tryptase+and chymase+, were statistically significant. The intralesional tryptase+ count showed an inverse correlation to age (R = –0.42); this correlation was the strongest in melanomas. The results obtained in our study suggest a possible correlation between mast cells and the pathogenesis of cutaneous melanoma

Hobnail hemangioma

We present a case of a 73-year-old woman who developed a small lesion on her tongue. The nodule was resected and hobnail hemangioma was diagnosed. Hobnail hemangioma is a rare vascular lesion with unusual morphology, including bland cells with hobnail appearance, biphasic grow pattern with superficial dilated vessels and slit-like vessels in the deeper portion of the lesion. The infiltrative pattern of grow may cause misdiagnosis. The differential diagnosis with hemangioendothelioma variants, low grade angiosarcomas and Kaposi sarcoma is of particular concern. The lack of recognition of this uncommon entity may result in excessive and unnecessary treatment

CD207+/langerin positive dendritic cells in invasive and in situ cutaneous malignant melanoma

Introduction: Dendritic cells are crucial for cutaneous immune response. Their role in melanoma progression is however a matter of controversy. Material and methods: The number of dendritic cells within epidermis and in peri- and intratumoral location was analyzed using CD207 immunostain in 17 cases of in situ and 25 case of invasive melanoma. Results: Average peritumoral CD207+ cells count was 22.88 for all cases, 17.94 for in situ lesions and 26.24 for invasive cases. Average epidermal CD207+ cells count was 164.47 for all cases, 183.00 for in situ lesions and 150.78 - for invasive cases. In case of invasive melanomas, peritumoral CD207+ cells count was positively correlated with Breslow stage (R = 0.59) mitotic activity within the tumor (R = 0.62). Invasive cases with regression showed higher intratumoral and epidermal CD207+ cells count than the ones without (275.00 vs. 95.32 and 173.20 vs. 148.35) but lower peritumoral CD207+ cells count (17.60 vs. 27.26). Invasive cases with ulceration showed higher intratumoral and peritumoral CD207+ cells count than the ones without ulceration (220.08 vs. 55.67 and 44.17 vs. 9.69). Conclusions: CD207+ cells play a role in both progression and regression of melanoma but their exact role needs further studies

Microvascular density and mast cells in benign and malignant pheochromocytomas

Pheochromocytomas, uncommon adrenal tumors, have an uncertain behavior. Recently, PASS criteria were proposed for differentiating between benign and malignant cases. These are not perfect, however. The aim of the study was to investigate angiogenesis and mast cell density in context of the clinical behavior and morphologic characteristics of pheochromocytomas. Mean intratumoral chymase positive cell count was 14.50 for malignant, 15.73 for benign cases; mean subcapsular chymase positive cell count was 12.50 for malignant, 11.27 for benign cases.Mean intratumoral tryptase positive cell count was 17.50 for malignant and 17.91 for benign cases; mean subcapsular tryptase positive cell count was 15.25 for malignant and 15.73 for benign cases.Mean intratumoral CD31 positive vessel count was 46.98 for malignant and 51.02 for benign cases; mean subcapsular CD31 positive vessel count was 44.86 for malignant and 39.81 for benign cases. Mean intratumoral CD105 positive vessel count was 37.84 for malignant and 35.95 for benign cases; mean subcapsular CD105 positive vessel count was 26.36 for malignant and 22.03 for benign cases. The differences between benign and malignant cases were not significant. All the vascular counts were correlated with mast cells counts. PASS index was inversely correlated with mast cell counts